(NASB) Acts 13:13 “Now Paul and his companions put out to sea from Paphos and came to Perga in Pamphylia; but John left them and returned to Jerusalem.”

In this one small and seemingly insignificant verse…what are we told about the three man team?  Paul becomes the leader of this group.  Barnabas was one of the men (Acts 13:1-2) and John Mark was with them as their helper.  (Acts 13:4-5)
We know the port from which they had sailed, Paphos on the western edge of Cyprus.  And we know the port to which they disembarked: Perga in Pamphylia (Turkey).
We know that at this point John Mark leaves and returns to his hometown of Jerusalem.

What we do not know from this verse:
Weather and sailing conditions…not a word.
Time of day they sailed…not a word.
Food and sleeping accommodations…not a word.
Seasickness or good health…not a word.
What we can know: their destination was of utmost importance to them.

Why did John Mark leave this important missionary journey?  We are not told.
However, from other Scripture we can make an educated guess…immaturity.
Paul was not happy with Mark, in fact we know he considered Mark a deserter.

When Paul and Barnabas were to set out on a second missionary journey, Barnabas wanted to take John Mark along…Paul adamantly refused…because Mark had deserted them during the first journey.  (Acts 15:36-38)
The disagreement was so sharp between Paul and Barnabas that they split up.  Paul chose another man, Silas to go with him.  Barnabas took John Mark and sailed to Cyprus.
(Acts 15:39-40)

Why did Mark desert?  Scripture never tells us.  Perhaps immaturity is the biggest reason; perhaps he couldn’t stand up to the rigors of travel and all the inconveniences of being away from home.  We just don’t know.  But desert he did.

Paul: did not put up with immature “attitudes” that hindered the mission.
Barnabas: was an encourager, possibly he nurtured Mark to mature him, to become a valuable contributor to God’s work.
John Mark: an immature younger man…the Lord used both Paul and Barnabas in his life to grow him up.

Later, many years later, Mark became an encourager to Paul.  (Colossians 4:10-11)  In fact, Paul even desired for Mark to be with him – for he had become useful for service.
(2 Timothy 4:11)

What is one possibility of why Mark became valuable to Paul?  Remember Barnabas took Mark “under his wing.”  Barnabas was an encourager.  Mark became teachable or he would not have become valuable to Paul.

Where are you in your walk with the Lord? 
Are you a Paul, one who doesn’t put up with immature attitudes; yet welcomes at a later date when those attitudes have changed?
Are you a Barnabas, one who encourages another to grow and become mature?
Are you a Mark, needing to mature and change into a valued member of your church?